* {
  margin: 0;
  padding: 0;
}

body {
  padding: 20px;
}

.box {
  position: relative;
  width: 800px;
  height: 600px;
  border: 1px solid red;
}

.box .menu {
  position: absolute;
  left: 0;
  top: 0;
  width: 150px;
  height: 200px;
  background-color: #00aeec;
}
